Question

In a thermodynamic process, a system absorbs 2 k cal of heat and at the same time does 800 J of work. The change in internal energy of the system is

• A. 7600 J
• B. 2000 J
• C. 4800 J
• D. -7600 J

Answer 1

The correct option is A 7600 J

In a thermodynamic process, a system absorbs 2 k cal of heat and at the same time does 800 J of work

By calorie to joules conversion

we have $1cal=4.2J$

$\therefore$$2Kcal=8400J$

Hence by first law of thermodynamics

we have,$\delta U=\delta H-W=8400-800=7600J$